Influence of water-cement ratio on the properties of 2-2 cement based piezoelectric composite

Composites with 2-2 connectivity were fabricated from plates of "PMN" ceramic embedded in a sulphoaluminate cement matrix by a cut-filling process. The influences of the water-cement ratio in the matrix on the properties of the composite were analyzed. The results show that when the water-cement ratio is less than 0.4, the piezoelectric stain factor d(33) and piezoelectric voltage factor 933 increase smoothly. When the water-cement ratio is larger than 0.4, d33 and 933 increase obviously with increasing the water-cement ratio. This is attributed to a more effective contact between the active and matrix phases. d(33) = 322 pc N-1 and g(33) = 20.9 mV mN(-1) at a water-cement ratio of 0.45. The planar electromechanical coupling coefficient K-p of the composite is nearly independent of the water-cement ratio. With increasing the water-cement ratio, the thickness electromechanical coupling coefficient Kt of the composite increases, while the mechanical quality factor Q exhibits the trend of decrease. (c) 2007 Elsevier B.V. All rights reserved.